readproctitle(8)

💖 NAME 💖

readproctitle — bestie, it keeps an automatically rotated log in memory so you can peek at it with ps(1) 🫶

readproctitle is available in daemontools 0.75 and above ✨

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🌸 SYNOPSIS 🌸

readproctitle L D

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🦋 DESCRIPTION 🦋

Okay so listen. L is literally any number of arguments. No cap. And D is one argument that has to contain at least five dots. That's the vibe check ✅

readproctitle reads data into the end of D, shifting D to the left to make room for it. The way that works means the most recent data is what's visible to process-listing tools like ps(1) 👀✨ And it always leaves three dots at the left of D, always, iconic behavior 💅

For example, if

readproctitle io errors: ....................

reads the data

fatal error xyz
warning abc

then its command-line arguments change to

readproctitle io errors: ... xyz!warning abc!

with a newline character in place of each ! 🎀 (so yes, there are literal newlines sitting in there now, not exclamation marks — the ! is just how the manpage shows you where they went)

Process-listing tools typically show the newline character as ? or \n. Not a glitch, that's just how they display it, iykyk 😭

readproctitle exits when it reaches the end of input. Periodt 🫡

⚠️ Beware bestie!! Most implementations of ps(1) have small argument-length limits, and those limits apply to the total length of readproctitle L D. The author has not seen a system with a limit below 512 bytes. So don't go feral and make D a novel, ok?? 🙈

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⭐ SEE ALSO ⭐

• supervise(8)
• svc(8)
• svok(8)
• svstat(8)
• svscanboot(8)
• svscan(8)
• fghack(8)
• pgrphack(8)
• multilog(8)
• tai64n(8)
• tai64nlocal(8)
• setuidgid(8)
• envuidgid(8)
• envdir(8)
• softlimit(8)
• setlock(8)
• ps(1)

🔗 http://cr.yp.to/daemontools.html 🔗 http://cr.yp.to/slashcommand.html

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okay that's the whole page bestie, mwah 💋 this was the readproctitle(8) entry from the System Manager's Manual, living in the daemontools 0.75-and-up era. go forth and rotate those logs in memory, you absolute main character 👑✨